How to get past activation screen on iphone 3GS?

I did a restore on my phone that I previous bought used and was jailbroken. I did a restore but now I can't get past activation screen. All I want to do is use it as an ipod but can't get past or skip the activation process. Is there a way to do this?

You can do the following:
-Re-jailbreak it (it will automatically get you past the screen.)
-Insert a sim card temporarily to get you past the screen